1. Field of the Invention
The present invention relates to a software architecture protocol stack for use in an ad-hoc wireless communication network. More particularly, the present invention relates to a protocol stack having embedded routing algorithms under the Internet Protocol (IP) routing layer, to thus provide high quality distribution of multimedia (voice, video, and data) services in a mobile wireless ad-hoc communications network.
2. Description of the Related Art
Many different types of wireless communication networks currently exists, such as wireless cellular telephone networks and the like. These types of wireless networks generally employ significant infrastructure, such as base stations, gateways, and so on, that communicate directly with wireless access devices that provide access to services such as the Internet, public switched telephone network (PSTN), and other cellular networks, to name a few. Examples of these types of networks are the current cellular communications networks, such as AMPS, TACS, NMT, GSM, IS-136 and IS-95.
In addition, certain cellular companies have developed networks called Wireless Access Protocol (WAP) networks that are capable of offering data services rather than only voice services. Furthermore, researchers have begun examining the application of ad-hoc networks for the delivery of multi-media content over wireless media. For example, in the Mobile Ad-Hoc Networking Group (MANET) of the Internet Engineering Task Force (IETF), researchers are applying the principles of ad-hoc routing on top of the Internet Protocol (IP), as described in a document by Johnson et al. entitled “The Dynamic Source Routing Protocol for Mobile Ad Hoc Networks”, in a document by Jacquet et al. entitled “Optimized Link Sate Routing Protocol”, and in a document by Perkins et al. entitled “Ad Hoc On-Demand Distance Vector (AODV) Routing”, the entire contents of each of these documents being incorporated herein by reference.
FIG. 1 is a conceptual diagram illustrating an example of a protocol stack 10 for a typical IETF-MANET Mobile Ad-Hoc Networking Group. The protocol stack 10 is implemented as a five-layer software stack, referenced from the bottom layer to the top. The lowest layer, the Physical Layer 12, includes the RF and modem circuits involved in generating channel quality information, such as a direct sequence spread spectrum (DSSS) modem with a 2.4 GHz radio frequency (RF) typically associated with code division multiple access (CDMA) systems. The Physical Layer 12 is responsible for transmitting and receiving configuration and application data with the Network Layer or Media Access Control (MAC) layer 14.
In a typical MANET protocol stack, the MAC layer 14 is specified in the IEEE 802.11 standard for wireless local area networks (LANs) and utilizes a Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol. As can be appreciated by one skilled in the art, the CSMA/CA protocol may involve initial handshakes of a Request-to-Send (RTS) message followed by a Clear-to-Send (CTS) or Not-Clear-to-Send (NCTS) message exchanged between a source node and a destination node prior to sending the multimedia (voice, video, data) message. Afterward, an Acknowledgement (ACK) message or Non-Acknowledgement (NACK) message may be sent from the destination node to the source node to indicate reception of the transmitted message. Layered above the MAC layer 14 is the routing internet protocol (IP) layer 16, which includes other Internet protocols schemes, such as Internet control message and Internet group management protocol.
In communication with the IP layer 16 is the transport layer 18 that defines the method of communicating. Well-known examples of the transport layer are TCP and UDP protocols. The uppermost layer, which is the application layer 20, provides application protocols, such as dynamic source routing (DSR) or ad-hoc on-demand distance vector routing (AODV) 20a, resource reservation protocol (RSVP) 20b, real time transport protocol (RTP) 20c, simple network management protocol (SNMP) 20d, dynamic host configuration protocol (DHCP) 20e, and authentication authorization and accounting protocol (AAA) 20f. 
Although the protocol stack 10 shown in FIG. 1 may be suitable for enabling a network to provide multimedia services, such as voice, video and data services, this type of protocol arrangement can be somewhat complex and time-consuming in terms of message delivery time and reliability. Therefore, this protocol stack arrangement has limited capability for commercial applications. Accordingly, a need exists for an improved protocol stack configuration which enables a wireless ad-hoc communication network to deliver multimedia content with sufficient speed and reliability suitable for use in commercial communication networks.